【摘要】 利用电荷自洽离散变分(SCC-DV-Xα)电子结构计算方法,计算TiFe储氢合金及其氢化物的电子结构,分析电子结构与储氢性能的相关性。结果表明,在TiFe合金氢化物中,H原子进入八面体晶胞中,H原子与Fe原子间成键作用明显比H原子与Ti原子间的成键作用强,使晶胞体积主要沿晶格的[110]方向发生膨胀;TiFe合金八面体晶胞中Ti原子与Fe原子间形成离域键,在吸氢后成键作用有所增强,使合金吸氢后的体积膨胀率较小,这是其反复吸放氢过程不容易粉化的原因之一。更多还原

【Abstract】 The electronic structures of TiFe hydrogen storage alloy and its hydride were calculated by SCC-DV-X_α(Self-Consistent-Charge discrete variation) method, and the correlation between the electronic structures and hydrogen storage properties was discussed in view of the nature of chemical bond.The results show that hydrogen atom makes a strong bond with Fe atoms rather than with Ti atoms,which causes lattice expansion mostly along \ direction while hydrogen occupies a central site of octahedron.In addition, the delocalized chemical bond formed among Fe atoms and Ti atoms in the unit cell is strengthened after absorbing hydrogen,it is the reason to cause a resistance to pulverization during absorbing and desorbing hydrogen repeatedly.更多还原